linux-kernel - [PATCH 002 of 5] knfsd: nfsd4: fix open permission checking

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Date:	Tue, 17 Oct 2006 09:30:15 +1000
From:	NeilBrown <neilb@...e.de>
To:	Andrew Morton <akpm@...l.org>
Cc:	nfs@...ts.sourceforge.net, linux-kernel@...r.kernel.org
Subject: [PATCH 002 of 5] knfsd: nfsd4: fix open permission checking


From: "J. Bruce Fields" <bfields@...ldses.org>
We weren't actually checking for SHARE_ACCESS_WRITE, with the result that
the owner could open a non-writeable file for write!

Continue to allow DENY_WRITE only with write access.

Thanks to Jim Rees for reporting the bug.

Signed-off-by: J. Bruce Fields <bfields@...i.umich.edu>
Signed-off-by: Neil Brown <neilb@...e.de>

### Diffstat output
 ./fs/nfsd/nfs4proc.c |    4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff .prev/fs/nfsd/nfs4proc.c ./fs/nfsd/nfs4proc.c
--- .prev/fs/nfsd/nfs4proc.c	2006-10-17 09:02:26.000000000 +1000
+++ ./fs/nfsd/nfs4proc.c	2006-10-17 09:04:13.000000000 +1000
@@ -78,8 +78,10 @@ do_open_permission(struct svc_rqst *rqst
 
 	if (open->op_share_access & NFS4_SHARE_ACCESS_READ)
 		accmode |= MAY_READ;
-	if (open->op_share_deny & NFS4_SHARE_ACCESS_WRITE)
+	if (open->op_share_access & NFS4_SHARE_ACCESS_WRITE)
 		accmode |= (MAY_WRITE | MAY_TRUNC);
+	if (open->op_share_deny & NFS4_SHARE_DENY_WRITE)
+		accmode |= MAY_WRITE;
 
 	status = fh_verify(rqstp, current_fh, S_IFREG, accmode);
 
-
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